Let them keep the truck there for another week or whatever gets you your 30 days.
Mfgs don't just hand out new rigs for free like candy, so I'd expect that your "non conformity" in their eyes does not render the vehicle out of service, unless of course you have proof it's sitting at the shop and they have the keys.
Besides, it's kind of a weak lemon law case to begin with. If they've agreed to remedy the problem and you don't truly need 4wd right now, then they're doing all they can and you're not really hurting, except emotionally, lol.
My only experience with this was with a truck that had a bad rear axle from the factory. Like locked up, smoked diff at like 500 mi. Major inconvienence even through the dealer took care of us. Was on the road hauling a trailer 150 mi form home.
Got the truck back, whole new 3rd member in it from wheel to wheel. This axle dos the same thing another 500 mi later, same trailer, now 400 mi form home in the opposite direction. Again great random dealer service on that one. Bent over backwards for me.
3rd axle was getting way too hot as well running empty. Hadn't towed hard n heavy with it. Took it in for arbitration (precedes lemon law in CO). They basically gave me every excuse in the book and threw me out on my ear! Fortunately the truck was pretty much flawless from then on for well over 100kmi and it was a non issue, but I felt it would have been a huge uphill battle that wouldn't have increased my roi on that truck significantly.
The other way to look at this is like insurance claims. Every person who tries to get their share, in questionable or cases or not out of necessity just helps raise the rates for everyone. Or the price of new cars as the case may be with lemon law.
Now if it really does stretch into months, then I agree with you, cause winters coming.
But even then I bet you could press them for a 4x4 loaner and look at it this way. If you don't NEED the truck right now, you're putting free miles, exept gas, on someone else's rig! Can you say time for a roadtrip?
Good luck with your issue.